Skouries is a high-grade gold-copper porphyry deposit located in the Halkidiki Peninsula in northern Greece.
It will operate as an open pit and underground mine for about nine years, followed by approximately 15 years of underground mining.
||Halkidiki Peninsula, Greece
||Open pit and underground
|Expected mine life
| Deposit type
|Resources & Reserves
* Based on current proven and probable reserves.
Construction at Skouries continues in 2017 with capital expenditures expected to be between $170.0 and $200.0 million. This is lower than September 2016 guidance mainly due to the flexibility in the capital plan in combination with cost initiatives that are underway. Funds will be used to continue the construction of the process plant and the integrated waste management facility.
Development of the decline is continuing, which will allow for extraction of material from the underground soon after the open pit start-up – currently scheduled for 2019.
Eldorado plans to develop Skouries in a two-phased approach. Production is targeted in 2019.
Phase 1 (2019-2027)
Phase 1 is a combination of open pit and underground mining over 9 years, producing a total of 1.4 million ounces of gold and 620 million pounds of copper at average cash operating costs of -$255 per ounce of gold due to copper by-product credits. Development capital over the Phase 1 is budgeted at $710 million and includes all mine development and process facilities.
Phase 2 (2028-2042)
Phase 2 involves underground mining for a 15 year period once Phase 1 is complete. Total production during this phase is expected to be 1.7 million ounces of gold and 850 million pounds of copper at average cash operating costs of $165 per ounce of gold due to copper by-product credits. Development capital during Phase 2 is budgeted at approximately $460 million.
Benefits of this updated development plan include:
- An increased feed to the plant, allowing it to run at full capacity (8 Mtpa) for a 14 year period, starting in 2020.
- Higher grades from the underground earlier on in the development.
- A smaller environmental footprint and decreased sustaining capex over the life of mine due to improved filtered tailings approach. A best-practice technology, filtered tailings decreases the amount of storage needed which potentially eliminates the need for a second storage facility.
- Improved project economics through optimized mine and tailings plans.
Please see our presentation Skouries Project for more information.
Geology and Mineralization
The Skouries porphyry gold-copper deposit is centred on a small (less than 400m in diameter), pencil-porphyry stock that intruded schist and gneiss of the Paleozoic Vertiskos Formation of the Serbo-Macedonian Massif, NE Greece. Mineralization extends for more than 920m depth from surface. The porphyry is characterized by at least four intrusive phases that are of probable monzonite to syenite composition,but contain an intense potassic alteration and related stockwork veining that overprints the original protolith. Potassic alteration and copper mineralization also extend into the country rock; approximately two thirds of the measured and indicated tonnes and 40% of the contained metal are hosted outside the porphyry. The potassic alteration is syn- to late-magmatic in timing, and is characterized by K-feldspar overgrowths on plagioclase, secondary biotite replacement of igneous hornblende and biotite, and a fine-grained groundmass of K-feldspar-quartz with disseminated magnetite. Four main stages of veining are recognised: 1) an early stage of intense quartz-magnetite stockwork; 2) quartz-magnetite veinlets with chalcopyrite ± bornite; 3) quartz-biotite-chalcopyrite ± bornite-apatite-magnetite veinlets; and 4) a localized, late stage set of pyrite ± chalcopyrite-calcite-quartz veins. The host porphyry and potassic alteration at Skouries were coeval and formed during the Early Miocene.
Exploration at Skouries is focused on identifying and testing porphyry targets within the project area, including the Tsikara and Fisoka prospects. Ongoing targeting activities include geological mapping, systematic soil sampling and geophysical surveying.